After a stormy start to the week for much of the East, a few dry days will be dampened by another round of rain, isolated flash flooding heading into the end of the workweek and the start of the weekend.
An area of low pressure impacting the Plains will begin moving east into the Great Lakes on Thursday evening, and by Friday morning before tracking through the Northeast with a trailing cold front extending from New York through the Ohio Valley and Midwest.
This front will serve as the focus for showers and downpours Friday afternoon.
With soils already saturated, and heavy rainfall rates expected, a Level 2 of 4 flash flood risk is in effect across parts of the Ohio Valley on both Friday and Saturday. The threat includes major cities such as St. Louis, Indianapolis, Cincinnati and Louisville.
On Saturday, the area of low pressure will continue east and be positioned near far eastern Maine. As the trailing cold front slows, instability will increase ahead of it while moisture surges northward from the Gulf and Atlantic Ocean.
Showers and downpours are expected to develop across the Mid-Atlantic and Northeast, including areas from Cincinnati, Ohio, to Washington, D.C., and New York City, during the afternoon.
By early Sunday, widespread rainfall totals of 1 to 2 inches are possible from southern Indiana through West Virginia, Pennsylvania and New Jersey. Localized amounts exceeding 2 to 3 inches could occur where slower-moving or training thunderstorms develop.
Some lingering showers are possible Sunday across parts of the Northeast with leftover instability in the atmosphere before drier and more seasonable weather is expected to return by Monday.